The present invention relates to blood sample collection and is directed particularly to improve devices used to collect and manually transfer blood, making them more efficient and reducing risk of blood contamination. The invention relates to an integrated assembly and apparatus for the collection of samples of blood specimens.
Historically, blood samples were taken by aspirating blood into a syringe and by manually transferring blood from the syringe into test tubes.
Vacuum-type blood sample collection tubes are used with tubular holders which have an internal threaded boss at one end to receive a double-ended sterile needle. The double-ended needle assembly has an upper transfer needle and an lower access needle which are joined at a base with external threads. First and second hard plastic covers with telescoping open ends cover the needles. Breaking a central seal by twisting the caps and pulling off the first cap exposes the rubber sleeve covered transfer needle and threaded base. Holding the second cap, which is interference-fit with cruciform flanges on the base, enables the engaging and tightening of the threads. The needle end, which fits through the boss and extends into the holder lumen, is covered with a thin flexible rubber cover. The lower access needle is covered with the second hard plastic cap. A vacuum-type collection tube is pushed part way into the holder with the stopper spaced from the upper needle. The hard cap is removed and the lower needle pierces a vein. Then the collection tube is pushed over the upper needle, and blood flows into the tube. With the holder in place, that tube may be removed and others may be pushed on the upper needle to obtain multiple samples.
The use of the small holder, although not difficult for trained medical technicians, requires finger strength and dexterity. Holding the holder in place with the lower needle in a vein while pushing and pulling vacuum-type blood sample collecting tubes may be mastered by medical technicians.
All medical professionals have experience in using standard syringes. The dexterity in using the syringes is the result of many repeated uses, both for sampling fluids and for injecting drugs, either directly from or into veins or from or into catheters.
In blood collection and sample tube filling for analysis and medical diagnosis or research, it is necessary to manually transfer blood from syringes to blood collection tubes. That is usually done by manual aspiration of blood from a catheter central line or vein into a syringe with a conventional plunger, followed by manual transfer of blood into vacuum-type blood collection tubes. This manual transfer increases the risk of blood contamination and the time required for blood collection procedure, consequently affecting the accuracy of blood test results. It also increases the risk of infecting the clinician as he/she holds a blood collection tube in her/his hand and forces a contaminated needle through its top. There is a great risk for an accidental needle stick during this process and consequent contamination of the clinician.
Direct venipuncture does not require manual transfer of blood to a collection tube since flashback of blood occurs readily. Collection of blood from a central line access requires manual aspiration of blood into a syringe and subsequent manual transfer into a blood collection tube. The devices available in the market will not simultaneously transfer a blood sample from a central line access to a tube since flashback of blood does not occur.
Collection of blood by means of direct venipuncture is not feasible in certain patients. In general, those patients suffer from severe and/or prolonged illnesses, like Hepatitis and AIDS.
Those diseases are highly contagious blood diseases which offer the most serious risk of contamination during manual transfer of the contaminated blood. During that transfer, a clinician must hold a blood collection tube in his hand and force a contaminated needle through its top, thus increasing the risk for an accidental needle stick.
A need exists for a syringe-related device which may be used to collect blood samples in vacuum-type blood sample collecting tubes.